This single-center, open-label study will assess the excretion balance, pharmacokinetics and metabolism of oral [14C]-labeled RO4917523 in healthy male volunteers. Subjects will receive a single oral dose of [14C]-labeled RO4917523 and an intravenous tracer dose of [13C]-labeled RO4917523 on Day 1. In-clinic period will be up to 18 Days. Anticipated time on study is up to 15 weeks.

Inclusion Criteria:

• Male adults, 18 to 65 years of age inclusive
• Body mass index (BMI) 18.0 to 32.0 kg/m2
• Healthy, as judged by a physician on the basis of a medical history, general physical examination, laboratory tests, vital signs and 12-lead ECG
• Medical history without major pathology
• Agree to use two effective methods of contraception with their partners, including one barrier method (e.g. condom) throughout the study and for up to 3 months after the last dose of study drug

Exclusion Criteria:

• History of relevant drug and or food allergies
• Smoking (within 60 days prior to drug administration until the follow-up visit)
• History of alcohol abuse or drug addiction (including soft drugs like cannabis products)
• Participation in a drug study within 60 days preceding first administration of study drug; participation in more than 3 other drug studies within 10 months preceding the first administration of study drug
• Infrequent bowel movements (less than once per 2 days)
• Participation in another ADME study with a radiation burden >0,1 mSv in the period of 1 years before the start of the study
• Positive screen for drugs of abuse
• Average intake of more than 24 units of alcohol per week
• Positive for hepatitis B, hepatitis C or HIV infection